glTF exporter: optimized anims can now be disabled

io_scene_gltf2/__init__.py

@@ -15,7 +15,7 @@
 bl_info = {
     'name': 'glTF 2.0 format',
     'author': 'Julien Duroure, Scurest, Norbert Nopper, Urs Hanselmann, Moritz Becher, Benjamin Schmithüsen, Jim Eckerlein, and many external contributors',
-    "version": (1, 8, 18),
+    "version": (1, 8, 19),
     'blender': (3, 1, 0),
     'location': 'File > Import-Export',
     'description': 'Import-Export as glTF 2.0',
@@ -390,6 +390,15 @@ class ExportGLTF2_Base:
         default=False
     )
 
+    optimize_animation_size: BoolProperty(
+        name='Optimize Animation Size',
+        description=(
+            "Reduces exported filesize by removing duplicate keyframes"
+            "Can cause problems with stepped animation"
+        ),
+        default=True
+    )
+
     export_current_frame: BoolProperty(
         name='Use Current Frame',
         description='Export the scene in the current animation frame',
@@ -582,11 +591,13 @@ class ExportGLTF2_Base:
             else:
                 export_settings['gltf_def_bones'] = False
             export_settings['gltf_nla_strips'] = self.export_nla_strips
+            export_settings['gltf_optimize_animation'] = self.optimize_animation_size
         else:
             export_settings['gltf_frame_range'] = False
             export_settings['gltf_move_keyframes'] = False
             export_settings['gltf_force_sampling'] = False
             export_settings['gltf_def_bones'] = False
+            export_settings['gltf_optimize_animation'] = False
         export_settings['gltf_skins'] = self.export_skins
         if self.export_skins:
             export_settings['gltf_all_vertex_influences'] = self.export_all_influences
@@ -874,6 +885,7 @@ class GLTF_PT_export_animation_export(bpy.types.Panel):
         layout.prop(operator, 'export_frame_step')
         layout.prop(operator, 'export_force_sampling')
         layout.prop(operator, 'export_nla_strips')
+        layout.prop(operator, 'optimize_animation_size')
 
         row = layout.row()
         row.active = operator.export_force_sampling

io_scene_gltf2/blender/exp/gltf2_blender_export_keys.py

@@ -57,6 +57,7 @@ EMBED_IMAGES = 'gltf_embed_images'
 BINARY = 'gltf_binary'
 EMBED_BUFFERS = 'gltf_embed_buffers'
 USE_NO_COLOR = 'gltf_use_no_color'
+OPTIMIZE_ANIMS = 'gltf_optimize_animation'
 
 METALLIC_ROUGHNESS_IMAGE = "metallic_roughness_image"
 GROUP_INDEX = 'group_index'

io_scene_gltf2/blender/exp/gltf2_blender_gather_animation_sampler_keyframes.py

@@ -318,6 +318,9 @@ def gather_keyframes(blender_object_if_armature: typing.Optional[bpy.types.Objec
 
             keyframes.append(key)
 
+    if not export_settings[gltf2_blender_export_keys.OPTIMIZE_ANIMS]:
+        return keyframes
+
     # For armature only
     # Check if all values are the same
     # In that case, if there is no real keyframe on this channel for this given bone,